Ethel Emma McMillanQSOJP (née Black, 12 May 1904 – 13 August 1987) was a New Zealand politician of the Labour Party. She was a Member of Parliament for Dunedin electorates for 22 years, but despite her political seniority, was not appointed a cabinet minister. She was very active in local affairs in Otago and was the first woman to be elected to Dunedin City Council.

After their wedding on 4 September 1929 at Gisborne, they settled in Kurow, where he had worked as a locum and then purchased the medical practice.[2] They moved to Dunedin in 1934, where her husband was elected to Parliament for the Labour Party in the Dunedin West electorate in 1935.[1] He was cabinet minister for a year, but retired from Parliament in 1943 to concentrate on his medical practice.[3] Gervan McMillan died from a heart disease in 1951, aged 46.[2]

During their time in Kurow, the McMillans had friendships and political discussions with their neighbours, Arnold Nordmeyer and Jerry Skinner; both would become influential MPs for the Labour Party. They also hosted Michael Joseph Savage, who in 1935 would become Prime Minister.[1] Her husband had been involved with the Labour Party since 1923,[2] and Ethel McMillan joined the party in about 1930.[1]

McMillan had a distinguished local career in Dunedin. She was the first woman to be elected onto Dunedin City Council in 1950 (the second woman was elected in 1970) and remained a councillor until 1980. In 1960, she became the first New Zealand woman to be appointed a trustee to a savings bank.[1] She chaired the local savings bank's board from 1964. She had governance roles with the Dunedin Public Art Gallery Society, the Otago Museum Trust, and the New Zealand Library Association.[1]